Metamath Proof Explorer


Theorem expimpd

Description: Exportation followed by a deduction version of importation. (Contributed by NM, 6-Sep-2008)

Ref Expression
Hypothesis expimpd.1 φψχθ
Assertion expimpd φψχθ

Proof

Step Hyp Ref Expression
1 expimpd.1 φψχθ
2 1 ex φψχθ
3 2 impd φψχθ